Repozytorium publikacji - Politechnika Gdańska

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Repozytorium publikacji
Politechniki Gdańskiej

Publikacje z roku 2020

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  • Nondestructive Testing of the Miter Gates Using Various Measurement Methods
    • Mikołaj Binczyk
    • Przemysław Kalitowski
    • Jakub Szulwic
    • Paweł Tysiąc
    2020 Pełny tekst SENSORS

    When any problems related to civil engineering structures appear, identifying the issue through the usage of only one measuring method is difficult. Therefore, comprehensive tests are required to identify the main source. The strains and displacement measurements, as well as modal identification, are widely used in the nondestructive testing of structures. However, measurements are usually carried out at several points and confirm or exclude only one of many potential causes of the problem. The main aim of this paper is to identify the causes of miter gates’ excessive vibration. The research includes displacement measurements using a tachometer and a laser scanner, acceleration measurements connected with modal analysis, and calculations with the finite element method (FEM) model. The numerical model underwent verification regarding test results. Particular attention was paid to evaluate the practical use of a laser scanner for diagnosing miter gates. Unlike classical methods, it measures many points. The analysis eliminated a number of potential causes of excessive vibration and highlighted the field of excessive deformation. The identified anomaly could be associated with bearings’ misalignment after closing the door. This construction part should be subjected to further research using classical methods. The laser scanning has been proven to be a method that can only generally present the deformation of the structure.


  • Non-Diophantine Arithmetics in Mathematics, Physics and Psychology
    • Mark Burgin
    • Marek Czachor
    2020

    For a long time, all thought there was only one geometry — Euclidean geometry. Nevertheless, in the 19th century, many non-Euclidean geometries were discovered. It took almost two millennia to do this. This was the major mathematical discovery and advancement of the 19th century, which changed understanding of mathematics and the work of mathematicians providing innovative insights and tools for mathematical research and applications of mathematics. A similar event happened in arithmetic in the 20th century. Even longer than with geometry, all thought there was only one conventional arithmetic of natural numbers — the Diophantine arithmetic, in which 2+2=4 and 1+1=2. It is natural to call the conventional arithmetic by the name Diophantine arithmetic due to the important contributions to arithmetic by Diophantus. Nevertheless, in the 20th century, many non-Diophantine arithmetics were discovered, in some of which 2+2=5 or 1+1=3. It took more than two millennia to do this. This discovery has even more implications than the discovery of new geometries because all people use arithmetic. This book provides a detailed exposition of the theory of non-Diophantine arithmetics and its various applications. Reading this book, the reader will see that on the one hand, non-Diophantine arithmetics continue the ancient tradition of operating with numbers while on the other hand, they introduce extremely original and innovative ideas.


  • Nonlinear dynamic analysis of the pure “buckling” mechanism during blow-out trauma of the human orbit
    • Marcin Zmuda Trzebiatowski
    • Paweł Kłosowski
    • Andrzej Skorek
    • Krzysztof Żerdzicki
    • Paweł Lemski
    • Mateusz Koberda
    2020 Pełny tekst Scientific Reports

    Considering the interplay between orbital bones and intraorbital soft tissues, commonly accepted patterns of the blow-out type of trauma within the human orbit require more thorough investigation to assess the minimal health-threatening impact value. Two different three-dimensional finite element method (FEM) models of the human orbital region were developed to simulate the pure “buckling” mechanism of orbital wall fracture in two variants: the model of orbital bone elements and the model of orbital bone, orbit and intraorbital tissue elements. The mechanical properties of the so-defined numerical skull fragment were applied to the model according to the unique laboratory tensile stress tests performed on small and fragile specimens of orbital bones as well as using the data available in the literature. The nonlinear transient analysis of the contact problem between bodies that differ substantially in terms of the Young’s modulus was carried out to investigate the interaction of different bodies within an instant injury. Potential damage areas were found within the lower orbital wall as well as the destructive load values for both FEM skull models (7,660 N and 8,520 N). Moreover, numerical simulations were validated by comparing them with computed tomography scans of real injuries.


  • Non-Linear Interaction of Harmonic Waves in a Quasi-Isentropic Flow of Magnetic Gas
    • Anna Perelomova
    2020 Pełny tekst Archives of Acoustics

    The diversity of wave modes in the magnetic gas gives rise to a wide variety of nonlinear phenomenaassociated with these modes. We focus on the planar fast and slow magnetosound waves in the geometryof a flow where the wave vector forms an arbitrary angleθwith the equilibrium straight magnetic field.Nonlinear distortions of a modulated signal in the magnetic gas are considered and compared to thatin unmagnetised gas. The case of acoustical activity of a plasma is included into consideration. Theresonant three-wave non-collinear interactions are also discussed. The results depend on the degree ofnon-adiabaticity of a flow,θ, and plasma-β.


  • Nonlinear numerical simulation of earthquake-induced pounding between timber frame buildings
    • Wojciech Migda
    • Marcin Szczepański
    • Natalia Lasowicz
    • Anna Jakubczyk-Gałczyńska
    • Robert Jankowski
    2020 AIP Conference Proceedings

    Earthquakes may induce serious dynamic loads acting on buildings, which can lead to damage or even destruction of the whole structure. In densely populated areas, it is quite common that buildings are located very close one to another which can result in pounding between them during ground motions. Due to the environmental awareness, multi-story timber frame buildings are gaining popularity and therefore there is a need to investigate the effects of structural collisions on seismic response of such buildings. In this paper, the results of advanced numerical FEM simulation, focused on inter-story pounding between two adjacent multi-story timber frame buildings, are presented. The results of the study show that structural interactions have a significant influence on the overall response of buildings exposed to damaging seismic excitations. Moreover, due to deformability of buildings made of wood, pounding may change response of such buildings much more, as compared to steel, reinforced concrete or masonry structures. Finally, the results confirm that the use of the nonlinear FEM with detailed representation of material and geometric structural properties can be considered as the effective approach in obtaining the accurate response of colliding timber frame buildings during earthquakes


  • Nonlocal Vibration of Carbon/Boron-Nitride Nano-hetero-structure in Thermal and Magnetic Fields by means of Nonlinear Finite Element Method
    • Hamid M. Sedighi
    • Mohammad Malikan
    • Ali Valipour
    • Krzysztof Kamil Żur
    2020 Pełny tekst Journal of Machinery Manufacture and Reliability

    Hybrid nanotubes composed of carbon and boron-nitride nanotubes have manifested as innovative building blocks to exploit the exceptional features of both structures simultaneously. On the other hand, by mixing with other types of materials, the fabrication of relatively large nanotubes would be feasible in the case of macroscale applications. In the current article, a nonlinear finite element formulation is employed to deal with the nonlocal vibrational behavior of carbon/boron-nitride nano-hetero-tubes in the presence of magneto-thermal environment. Euler-Bernoulli beam model in conjunction with the Eringen's nonlocal theory of elasticity is adopted to derive the governing equation of motion. In order to conduct a nonlinear frequency analysis, the von-Kármán nonlinearity associated with moderate rotations is also considered. It is well-known that temperature gradients can significantly change the dynamic behavior of nanotubes. On the other hand, the coefficients of thermal expansions of carbon and boron-nitride nanotubes are quite different which may affect the structural stability of hybrid nanotubes. Hence, to explore the vibration characteristic of such composite structures, the influence of magneto-thermal environment is also taken into account. Finally, the eigenvalue analysis is performed to exhibit the nonlinear mode shapes and natural frequencies of the system due to initial displacement. It is expected that the recognition of dynamic behavior of such hybrid nanotubes may open the doors to the creative design of next-generation nanodevices.


  • Nonreciprocal cavities and the time-bandwidth limit: comment
    • Kosmas L. Tsakmakidis
    • Yun You
    • Tomasz Stefański
    • Linfang Shen
    2020 Pełny tekst Optica

    In their paper in Optica 6, 104 (2019), Mann et al. claim that linear, time-invariant nonreciprocal structures cannot overcome the time-bandwidth limit and do not exhibit an advantage over their reciprocal counterparts, specifically with regard to their time-bandwidth performance. In this Comment, we argue that these conclusions are unfounded. On the basis of both rigorous full-wave simulations and insightful physical justifications, we explain that the temporal coupled-mode theory, on which Mann et al. base their main conclusions, is not suited for the study of nonreciprocal trapped states, and instead direct numerical solutions of Maxwell’s equations are required. Based on such an analysis, we show that a nonreciprocal terminated waveguide, resulting in a trapped state, clearly outperforms its reciprocal counterpart; i.e., both the extraordinary time-bandwidth performance and the large field enhancements observed in such modes are a direct consequence of nonreciprocity.


  • Non-Salient Brushless Synchronous Generator Main Exciter Design for More Electric Aircraft
    • Filip Kutt
    • Michał Michna
    • Grzegorz Kostro
    2020 Pełny tekst ENERGIES

    This paper presents a prototype of high speed brushless synchronous generators (BSG) design for the application in autonomous electric power generation systems (e.g., airplane power grid). Commonly used salient pole field of the main generator part of BSG was replaced with a prototype non-salient pole field. The main objective of the research is an investigation into the advantages and disadvantages of a cylindrical field of the main generator part of BSG over the original salient pole field. The design process of the prototype generator is presented with a focus on the electromagnetic and mechanical finite element method (FEM) analysis. The measurements of prototype and commercial BSG were conducted for the nominal speed of 8 krpm. The advantages and disadvantages of the proposed solution were established based on measurements in load and no-load conditions.


  • Non-standard contact conditions in generalized continua: microblock contact model for a Cosserat body
    • Maciej Lewandowski-Szewczyk
    • S. Stupkiewicz
    2020 Pełny tekst INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

    Generalized continuum theories involve non-standard boundary conditions that are associated with the additional kinematic variables introduced in those theories, e.g., higher gradients of the displacement field or additional kinematic degrees of freedom. Accordingly, formulation of a contact problem for such a continuum necessarily requires that adequate contact conditions are formulated for the additional kinematic variables and/or for the respective generalized tractions. In this paper, we address several related open problems, namely, how to enhance the classic contact conditions to include the effects of the additional kinematic variables, how to link the enhanced contact model to the underlying microstructure of the solid, and how to do it in a consistent manner. As a first step towards a new class of contact models for generalized continua, a microblock contact model is derived for a Cosserat solid based on simple micromechanical considerations. To illustrate the non-trivial effects introduced by the non-standard boundary conditions, the problem of compression of an infinite strip with nonaligned microblocks is considered, and the analytical solution is derived for the corresponding boundary layers. A Hertz-like contact problem is also solved numerically with the focus on non-standard features of the solution and on the related size effects.


  • Normy i szkolenia z normalizacji w Bibliotece PG
    • Janusz Waluszko
    2020 Pismo PG

    Tekst omawia znaczenie norm dla studentów i naukowców oraz szkolenia z normalizacji organizowane przez Bibliotekę Politechniki Gdańskiej


  • Novel 1,2,4-Oxadiazole Derivatives in Drug Discovery
    • Karol Biernacki
    • Mateusz Daśko
    • Olga Ciupak
    • Konrad Kubiński
    • Janusz Rachoń
    • Sebastian Demkowicz
    2020 Pełny tekst Pharmaceuticals

    Abstract: Five-membered 1,2,4-oxadiazole heterocyclic ring has received considerable attention because of its unique bioisosteric properties and an unusually wide spectrum of biological activities. Thus, it is a perfect framework for the novel drug development. After a century since the 1,2,4-oxadiazole have been discovered, the uncommon potential attracted medicinal chemists’ attention, leading to the discovery of a few presently accessible drugs containing 1,2,4-oxadiazole unit. It is worth noting that the interest in a 1,2,4-oxadiazoles’ biological application has been doubled in the last fifteen years. Herein, after a concise historical introduction, we present a comprehensive overview of the recent achievements in the synthesis of 1,2,4-oxadiazole-based compounds and the major advances in their biological applications in the period of the last five years as well as brief remarks on prospects for further development.


  • Novel ABTS-dot-blot method for the assessment of antioxidant properties of food packaging
    • Barbara Kusznierewicz
    • Hanna Staroszczyk
    • Edyta Malinowska-Pańczyk
    • Karol Parchem
    • Agnieszka Bartoszek-Pączkowska
    2020 Pełny tekst Food Packaging and Shelf Life

    The new ABTS-dot-blot method for the direct determination of antioxidant activity of active packaging that is in contact with foodstuffs has been developed. The usefulness of the new method was verified with the use of agarose, pork gelatin, bacterial cellulose and cellulose-chitosan films with incorporated standard antioxidant – Trolox or plant phytochemicals derived from three types of berry juices (chokeberry, blue-berried honeysuckle, rowanberry) or green tea. The plant components used for preparation of films were characterized by antioxidant profiling with the use of HPLC coupled with post-column derivatization with ABTS. The most abundant antioxidants were polyphenols, mainly anthocyanins, hydroxycinnamates and flavan-3-ols. The antioxidant properties of different types of films studied were evaluated by typical cuvette spectrophotometric ABTS test or by the novel method employing ABTS radical stabilised in an agarose gel. The results obtained for the Trolox containing films showed quantitative linear relationship between antioxidant content and the degree of ABTS bleaching in agarose gel. The results of both standard spectrophotometric method as well as ABTS-dot-blot approach indicated that gelatin, bacterial cellulose and chitosan on their own possessed antioxidant activity, which was substantially increased (6–10 times) by the addition of phytochemicals during film preparation. The highest antioxidant activity was observed for microbial cellulose films, which were prepared on the basis of material obtained during the kombucha drink production.


  • Novel application of dynamic electrochemical impedance monitoring to a cataphoretic coating process
    • Kazimierz Darowicki
    • Paweł Ślepski
    • Michał Szociński
    2020 Pełny tekst PROGRESS IN ORGANIC COATINGS

    The paper presents a novel method of on-line impedance monitoring of cataphoretic coating application process. Utilization of dynamic electrochemical impedance spectroscopy (DEIS) overcame the fundamental problem connected with non-stationarity of the aforementioned coating deposition process, which eliminates classical impedance spectroscopy technique from a real-time description of cataphoresis. The paper illustrates selected examples of potentialities of DEIS regarding the characterization of the cataphoretic coating process. Acquired instantaneous impedance spectra enabled on-line insight into impedance changes upon steel substrate polarization duration, thus visualizing coating application progress. DEIS allowed estimation of the time necessary for the coating/steel substrate system to achieve a steady state after polarization switch off. The proposed approach seems to be a step towards real-time monitoring of electrophoretic coating application and offers a potential for improved process control and optimization.


  • Novel approach to interference analysis of glucose sensing materials coated with Nafion
    • Adrian Olejnik
    • Jakub Karczewski
    • Anna Dołęga
    • Katarzyna Siuzdak
    • Katarzyna Grochowska
    2020 BIOELECTROCHEMISTRY

    A gold-based sensing platform, TiND | AuNP | Nafion, was prepared as an exemplary electrode material exhibiting a response to glucose in a neutral solution. The change of electrochemical properties after exposure to glucose and interference compounds such as vitamin C, glycine, urea, paracetamol and acetylsalicylic acid was tested.


  • Novel Class of Proton Conducting Materials—High Entropy Oxides
    • Maria Gazda
    • Tadeusz Miruszewski
    • Daniel Jaworski
    • Aleksandra Dorota Mielewczyk-Gryń
    • Wojciech Skubida
    • Sebastian Lech Wachowski
    • Piotr Winiarz
    • Kacper Dzierzgowski
    • Marcin Stanisław Łapiński
    • Iga Szpunar
    • Ewa Dzik
    2020 Pełny tekst ACS Materials Letters

    Here, for the first time, we present data on proton conductivity of high-entropy, single-phase perovskites. The BaZr0.2Sn0.2Ti0.2Hf0.2Ce0.2O3−δ, BaZr0.2Sn0.2Ti0.2Hf0.2Y0.2O3−δ, BaZr1/7Sn1/7Ti1/7Hf1/7Ce1/7Nb1/7Y1/7O3−δ, and BaZr0.15Sn0.15Ti0.15Hf0.15Ce0.15Nb0.15Y0.10O3−δ single-phase perovskites were synthesized. Before electrical measurements, materials were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The following experimental results demonstrated that studied high-entropy perovskites are proton conductors: (1) The observed mass increase upon the switch from dry to wet atmosphere confirmed the water incorporation into materials structure. (2) The electrochemical impedance spectroscopy (EIS) revealed that the total conductivity increased while its activation energy decreased in the presence of water vapor in the atmosphere. (3) The conductivity in atmosphere humidified with H2O and D2O differed one from another, showing typical of proton conductors isotope effect in high-entropy oxides.


  • Novel Fault Identification for Electromechanical Systems via Spectral Technique and Electrical Data Processing
    • Tomasz Ciszewski
    • Len Gelman
    • Andrew Ball
    2020 Pełny tekst Electronics

    It is proposed, developed, investigated, and validated by experiments and modelling for the first time in worldwide terms new data processing technologies, higher order spectral multiple correlation technologies for fault identification for electromechanical systems via electrical data processing. Investigation of the higher order spectral triple correlation technology via modelling has shown that the proposed data processing technology effectively detects component faults. The higher order spectral triple correlation technology successfully applied for rolling bearing fault identification. Experimental investigation of the technology has shown, that the technology effectively identifies rolling bearing fault by electrical data processing at very early stage of fault development. Novel technology comparisons via modelling and experiments of the proposed higher order spectral triple correlation technology and the higher order spectra technology show the higher fault identification effectiveness of the proposed technology over the bicoherence technology.


  • Novel MNZ-type microwave sensor for testing magnetodielectric materials
    • Abhishek Jha
    • Nicolò Delmonte
    • Adam Lamęcki
    • Michał Mrozowski
    • Maurizzio Bozzi
    2020 Pełny tekst Scientific Reports

    A novel microwave sensor with the mu-near-zero (MNZ) property is proposed for testing magnetodielectric material at 4.5 GHz. The sensor has a double-layer design consisting of a microstrip line and a metal strip with vias on layers 1 and 2, respectively. The proposed sensor can detect a unit change in relative permittivity and relative permeability with a difference in the operating frequency of 45 MHz and 78 MHz, respectively. The MNZ sensor is fabricated and assembled on two layers of Taconic RF-35 substrate, with thicknesses of 0.51 mm and 1.52 mm, respectively, for the measurement of the sample under test using a vector network analyzer. The dielectric and magnetic properties of two standard dielectric materials (Taconic CER-10 and Rogers TMM13i) and of yttrium–gadolinium iron garnet are measured at microwave frequencies. The results are found to be in good agreement with the values available in the literature, which shows the applicability of the prototype for sensing of magnetodielectric materials.


  • Novel N-(aryl/heteroaryl)-2-chlorobenzenesulfonamide derivatives: synthesis and anticancer activity evaluation
    • Anita Bułakowska
    • Jarosław Sławiński
    • Kamila Siedlecka-Kroplewska
    • Grzegorz Stasiłojć
    • Marcin Serocki
    • Mateusz Heldt
    2020 BIOORGANIC CHEMISTRY

    A new series of N-(aryl/heteroaryl)-2-chlorobenzenesulfonamide derivatives 4-21 have been synthesized, and evaluated at the National Cancer Institute (USA) for their in vitro activities against a panel of 60 different human cancer cell lines. Among them, compounds 16, 20 and 21 exhibited remarkable cytotoxic activity against numerous human cancer cell lines. We found that sulfonamide derivative 21 appeared to be more selective than compounds 16 and 20. In comparison to compounds 16 and 20 it showed higher cytotoxic activity against A549 non-small cell lung adenocarcinoma and HCT-116 colon carcinoma cells and was less toxic to HEK-293 human embryonic kidney cells and HaCaT immortalized human keratinocytes. Treatment of A549 and HCT-116 cells with compound 21 resulted in the G0/G1-cell cycle arrest with a concomitant increase in p53 and p21 protein levels. Moreover, compound 21 led to ATP depletion and disruption of the mitochondrial membrane potential in both studied cell lines. Our results suggest that 2,4-dichloro-N-(quinolin-8-yl and/or 1H-indazol-7-yl)benzenesulfonamides serve as novel promising anticancer agents.


  • Novel tetrahedral cobalt(II) silanethiolates: structures and magnetism
    • Daria Kowalkowska-Zedler
    • Natalia Nedelko
    • Katarzyna Kazimierczuk
    • Pavlo Aleshkevych
    • Renata Łyszczek
    • Anna Ślawska-waniewska
    • Agnieszka Pladzyk
    2020 Pełny tekst RSC Advances

    Three heteroleptic complexes of Co(II) tri-tert-butoxysilanethiolates have been synthesized with piperidine [Co{SSi(OtBu)3}2(ppd)2] 1, piperazine [Co{SSi(OtBu)3}2(NH3)]2(μ-ppz)·2CH3CN 2, and N-ethylimidazole [Co{SSi(OtBu)3}2(etim)2] 3. The complexes have been characterized by a single-crystal X-ray, revealing their tetrahedral geometry on Co(II) coordinated by two nitrogen and two sulfur atoms. Complexes 1 and 3 are mononuclear, whereas 2 is binuclear. The spectral properties and thermal properties of 1–3 complexes were established by FTIR spectroscopy for solid samples and TGA. The magnetic properties of complexes 1, 2, and 3 have been investigated by static magnetic measurements and X-band EPR spectroscopy. These studies have shown that 1 and 3, regardless of the similarity in structure of CoN2S2 cores, demonstrate different types of local magnetic anisotropy. Magnetic investigations of 2 reveal the presence of weak antiferromagnetic intra-molecular Co(II)–Co(II) interactions that are strongly influenced by the local magnetic anisotropy of individual Co(II) ions.


  • Nowa koncepcja płaszczowo-rurowego wymiennika ciepła z techniką strugową w rurach pęku
    • Jan Wajs
    • Roksana Bochniak
    2020

    W pracy przedstawiono nowe podejście do implementacji techniki strugowej w wymiennikach cylindrycznych. Obiektem badań jest opatentowana konstrukcja płaszczowo-rurowego wymiennika ciepła z techniką strugową obecną w rurach pęku. Generatorem strug są perforowane wkłady rurowe, w których średnica pojedynczego otworu wynosi 1.3 mm. Dla poprawy kompaktowości tego wymiennika, perforowane wkłady wykonano w technologii minikanałowej – ich średnica wewnętrzna wynosi 2 mm. Omówiono budowę i zasadę działania wymiennika, przedstawiono stanowisko pomiarowe do prowadzenia badań cieplno-przepływowych oraz omówiono wyniki wstępnych badań konwekcji jednofazowej w układzie gaz-ciecz. Wyniki te posłużyły do weryfikacji korelacji dostępnych w literaturze przedmiotu.